Tulane National Primate Research Center (TNPRC) has one of the largest rhesus monkey breeding colonies in the US. This resource has provided animals for NIH funded research projects for several decades and is a critical component of the Center's successful research program. Because over half of all research projects at TNPRC are initiated by Affiliate (outside) investigators, this resource is also essential to the success of many NIH-funded investigators throughout the country. The objective of this application is to request funds for continued support and maintenance of this SPF rhesus monkey breeding colony at the TNPRC. The maintenance of the U42 breeding colony requires the integration of many aspects of the animal care program at TNPRC including veterinary care, behavioral management, genetic monitoring, and viral testing to ensure SPF status of the colony. This section describes the husbandry and management of the colony and focuses on daily care operations, behavioral management, and clinical care. The Specific Aim of this core is to provide husbandry and veterinary care for the SPF breeding colony established in the existing U42 grant. This includes a robust program for clinical care and behavioral management. The colony has reached a mature status of approximately 800 animals with ideal demographics to produce up to 150 animals available for assignment each year. Program Income generated by the sale of animals will be returned to an account for use in supporting the aims of the grant.